Add artist implementation that lazily loads referenced objects.
[demoscenemusic.git] / src / main / java / net / pterodactylus / demoscenemusic / data / DataManager.java
1 /*
2  * DemosceneMusic - DataManager.java - Copyright © 2012 David Roden
3  *
4  * This program is free software: you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License as published by
6  * the Free Software Foundation, either version 3 of the License, or
7  * (at your option) any later version.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
16  */
17
18 package net.pterodactylus.demoscenemusic.data;
19
20 import java.sql.ResultSet;
21 import java.sql.SQLException;
22 import java.util.ArrayList;
23 import java.util.Collection;
24 import java.util.HashSet;
25 import java.util.List;
26 import java.util.concurrent.Callable;
27
28 import net.pterodactylus.util.collection.Memoizer;
29 import net.pterodactylus.util.database.Database;
30 import net.pterodactylus.util.database.DatabaseException;
31 import net.pterodactylus.util.database.Field;
32 import net.pterodactylus.util.database.Join;
33 import net.pterodactylus.util.database.Join.JoinType;
34 import net.pterodactylus.util.database.OrderField;
35 import net.pterodactylus.util.database.OrderField.Order;
36 import net.pterodactylus.util.database.Parameter.StringParameter;
37 import net.pterodactylus.util.database.Query;
38 import net.pterodactylus.util.database.Query.Type;
39 import net.pterodactylus.util.database.ResultProcessor;
40 import net.pterodactylus.util.database.ValueField;
41 import net.pterodactylus.util.database.ValueFieldWhereClause;
42
43 /**
44  * TODO
45  *
46  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
47  */
48 public class DataManager {
49
50         private final Database database;
51
52         public DataManager(Database database) {
53                 this.database = database;
54         }
55
56         public Collection<Artist> getAllArtists() throws DatabaseException {
57                 Query query = new Query(Type.SELECT, "ARTISTS");
58                 query.addField(new Field("ARTISTS.*"));
59                 query.addField(new Field("GROUP_ARTISTS.*"));
60                 query.addField(new Field("GROUPS.*"));
61                 query.addJoin(new Join(JoinType.INNER, "GROUP_ARTISTS", new Field("ARTISTS.ID"), new Field("GROUP_ARTISTS.ARTIST")));
62                 query.addJoin(new Join(JoinType.INNER, "GROUPS", new Field("GROUP_ARTISTS.GROUP_"), new Field("GROUPS.ID")));
63                 query.addOrderField(new OrderField(new Field("ARTISTS.ID")));
64                 ArtistLoader artistLoader = new ArtistLoader();
65                 database.process(query, artistLoader);
66                 return artistLoader.all();
67         }
68
69         public Artist getArtistById(String id) throws DatabaseException {
70                 Query query = new Query(Type.SELECT, "ARTISTS");
71                 query.addField(new Field("ARTISTS.*"));
72                 query.addField(new Field("GROUP_ARTISTS.*"));
73                 query.addField(new Field("GROUPS.*"));
74                 query.addJoin(new Join(JoinType.INNER, "GROUP_ARTISTS", new Field("ARTISTS.ID"), new Field("GROUP_ARTISTS.ARTIST")));
75                 query.addJoin(new Join(JoinType.INNER, "GROUPS", new Field("GROUP_ARTISTS.GROUP_"), new Field("GROUPS.ID")));
76                 query.addWhereClause(new ValueFieldWhereClause(new ValueField("ARTISTS.ID", new StringParameter(id))));
77                 query.addOrderField(new OrderField(new Field("ARTISTS.ID")));
78                 ArtistLoader artistLoader = new ArtistLoader();
79                 database.process(query, artistLoader);
80                 return artistLoader.get();
81         }
82
83         public Track trackById(String id) throws DatabaseException {
84                 Query query = new Query(Type.SELECT, "TRACKS");
85                 query.addField(new Field("TRACKS.*"));
86                 query.addField(new Field("TRACK_ARTISTS.*"));
87                 query.addField(new Field("ARTISTS.*"));
88                 query.addField(new Field("TRACK_STYLES.*"));
89                 query.addField(new Field("STYLES.*"));
90                 query.addJoin(new Join(JoinType.INNER, "TRACK_ARTISTS", new Field("TRACKS.ID"), new Field("TRACK_ARTISTS.TRACK")));
91                 query.addJoin(new Join(JoinType.INNER, "ARTISTS", new Field("TRACK_ARTISTS.ARTIST"), new Field("ARTISTS.ID")));
92                 query.addJoin(new Join(JoinType.INNER, "TRACK_STYLES", new Field("TRACKS.ID"), new Field("TRACK_STYLES.TRACK")));
93                 query.addJoin(new Join(JoinType.INNER, "STYLES", new Field("TRACK_STYLES.STYLE"), new Field("STYLES.ID")));
94                 query.addWhereClause(new ValueFieldWhereClause(new ValueField("TRACKS.ID", new StringParameter(id))));
95                 query.addOrderField(new OrderField(new Field("TRACKS.ID"), Order.ASCENDING));
96                 query.addOrderField(new OrderField(new Field("TRACK_ARTISTS.DISPLAY_ORDER"), Order.ASCENDING));
97                 TrackLoader trackLoader = new TrackLoader();
98                 database.process(query, trackLoader);
99                 return trackLoader.get();
100         }
101
102         public Collection<Track> getTracksByArtist(String artistId) throws DatabaseException {
103                 Query query = new Query(Type.SELECT, "TRACKS");
104                 query.addField(new Field("TRACKS.*"));
105                 query.addField(new Field("TRACK_ARTISTS.*"));
106                 query.addField(new Field("ARTISTS.*"));
107                 query.addField(new Field("TRACK_STYLES.*"));
108                 query.addField(new Field("STYLES.*"));
109                 query.addJoin(new Join(JoinType.INNER, "TRACK_ARTISTS", new Field("TRACKS.ID"), new Field("TRACK_ARTISTS.TRACK")));
110                 query.addJoin(new Join(JoinType.INNER, "ARTISTS", new Field("TRACK_ARTISTS.ARTIST"), new Field("ARTISTS.ID")));
111                 query.addJoin(new Join(JoinType.INNER, "TRACK_STYLES", new Field("TRACKS.ID"), new Field("TRACK_STYLES.TRACK")));
112                 query.addJoin(new Join(JoinType.INNER, "STYLES", new Field("TRACK_STYLES.STYLE"), new Field("STYLES.ID")));
113                 query.addWhereClause(new ValueFieldWhereClause(new ValueField("ARTISTS.ID", new StringParameter(artistId))));
114                 query.addOrderField(new OrderField(new Field("TRACKS.ID"), Order.ASCENDING));
115                 query.addOrderField(new OrderField(new Field("TRACK_ARTISTS.DISPLAY_ORDER"), Order.ASCENDING));
116                 TrackLoader trackLoader = new TrackLoader();
117                 database.process(query, trackLoader);
118                 return trackLoader.all();
119         }
120
121         private class TrackLoader implements ResultProcessor {
122
123                 private final List<Track> loadedTracks = new ArrayList<Track>();
124                 private Track track;
125
126                 public Track get() {
127                         return loadedTracks.isEmpty() ? null : loadedTracks.get(0);
128                 }
129
130                 public List<Track> all() {
131                         return loadedTracks;
132                 }
133
134                 /**
135                  * {@inheritDoc}
136                  */
137                 public void processResult(ResultSet resultSet) throws SQLException {
138                         String trackId = resultSet.getString("TRACKS.ID");
139                         if ((track == null) || (!track.id().equals(trackId))) {
140                                 track = new DefaultTrack(trackId).name(resultSet.getString("TRACKS.NAME")).artists(new ArrayList<Artist>()).styles(new HashSet<Style>());
141                                 loadedTracks.add(track);
142                         }
143                         Artist artist = new DefaultArtist(resultSet.getString("ARTISTS.ID")).name(resultSet.getString("ARTISTS.NAME"));
144                         if (!track.artists().contains(artist)) {
145                                 track.artists().add(artist);
146                         }
147                         Style style = new DefaultStyle(resultSet.getString("STYLES.ID")).name(resultSet.getString("STYLES.NAME"));
148                         track.styles().add(style);
149                 }
150
151         }
152
153         private class ArtistLoader implements ResultProcessor {
154
155                 private final List<Artist> artists = new ArrayList<Artist>();
156                 private Artist artist;
157
158                 public Artist get() {
159                         return artists.isEmpty() ? null : artists.get(0);
160                 }
161
162                 public List<Artist> all() {
163                         return artists;
164                 }
165
166                 //
167                 // RESULTPROCESSOR METHODS
168                 //
169
170                 /**
171                  * {@inheritDoc}
172                  */
173                 public void processResult(ResultSet resultSet) throws SQLException {
174                         String artistId = resultSet.getString("ARTISTS.ID");
175                         if ((artist == null) || (!artist.id().equals(artistId))) {
176                                 artist = new DefaultArtist(artistId).name(resultSet.getString("ARTISTS.NAME")).groups(new HashSet<Group>());
177                                 artists.add(artist);
178                         }
179
180                         Group group = new DefaultGroup(resultSet.getString("GROUPS.ID")).name(resultSet.getString("GROUPS.NAME")).url(resultSet.getString("GROUPS.URL"));
181                         artist.groups().add(group);
182                 }
183
184         }
185
186         private class LazyArtist extends DefaultArtist {
187
188                 private final Memoizer<Void> tracks = new Memoizer<Void>(new Callable<Void>() {
189                         public Void call() throws DatabaseException {
190                                 if (!hasValue("tracks")) {
191                                         value("tracks", Collection.class).set(getTracksByArtist(id()));
192                                 }
193                                 return null;
194                         }
195                 });
196
197                 public LazyArtist(String id) {
198                         super(id);
199                 }
200
201                 public Collection<Track> tracks() {
202                         tracks.get();
203                         return value("tracks", Collection.class).get();
204                 }
205
206         }
207
208 }